Electromechanical transducers having a cantilever (a beam supported at one end) structure are known that have a thin film of a piezoelectric material formed on a plate. They permit efficient conversion of expansive-contractive deformation along the plane of the thin film into a displacement in the direction perpendicular to the plane, and thus allow the building of highly sensitive sensors and actuators. Inconveniently, however, since one end of the beam is loose, they are not very rigid and are prone to be deformed and twisted under external forces.
As solutions, different improvements have been proposed to increase the rigidity of the displacement film, such as a portal (a beam supported at both ends) structure where the displacement film is held at opposite ends and a diaphragm structure where the displacement film is held around its edge. This increases the rigidity of the displacement film, and leads to the following advantages: the generated force is increased; deformation occurs stably under external forces; a central part of the displacement film can be moved parallel to the plate; the hermetic structure allows application in pumps for transporting gas and liquid; etc.
On the other hand, ink-jet printers are known that are provided with a plurality of channels for jetting out liquid ink and that control the jetting of ink while moving relative to a recording medium such as paper and cloth so as to thereby output two-dimensional images. For fast image formation on such printers, a line-head system is preferable in which scanning is performed in one direction with channels arranged across the entire width of the recording medium.
With a line-head system, to reduce the cost of the head and achieve high resolution, it is preferable to make the channels as small as possible and arrange small channels two-dimensionally in the head with high density. As a method of making channels small and increase their density, Patent Document 1 listed below proposes a method in which square channels are arranged in a staggered formation.
On the other hand, Patent Documents 2 and 3 listed below disclose ink-jet-type recording heads in which a piezoelectric member held between a lower and an upper electrode is provided over an elongate pressurizing chamber. In these ink-jet-type recording heads, the piezoelectric member and the upper electrode are extended in the length direction of the pressurizing chamber to lead out wiring for electrical connection.